- "Unlike the Mask of Disguise, this spell actually allows me to cast away the guise of death for a time, allowing me to walk among the living undisturbed. The spell also provides a visage of nobility, for there are many who would easily divulge more to those of highborn blood."
- ―Kain — Listen (file info)
Beguile was effectively an upgrade of Kain's Disguise Form (which Kain was unable to use after gaining Beguile). The spell, though counted as a 'Form' did not actually transform Kain at all, instead it allowed Kain to cast off the visage of death, and appear to other characters as a Human nobleman.
When travelling to Willendorf, Kain found that the walled city only allowed those of noble blood inside it walls. Kain was therefore forced to investigate Willendorf's nearby Provincial Mines, where he found a tomb containing an ancestor of Willendorf's King Ottmar and a blood fountain which 'upgraded the Disguise Form to the Beguile ability, allowing Kain to enter Willendorf City and gain an audience with Ottmar.
The Beguile Form featured slightly different icons than its predecessor, Disguise, featuring a small 'shield' in the top corner to distinguish the two, Kain also had a 'mask' icon above his head when using this spell. When using the Beguile Form, Kain was able to attack enemies, without reprisal (unless he attacked Human guards).
Kain hints in his description of the form that he actually casts off the "guise of death". This may mean that the "visage of nobility" this form brings may actually be as a result of Kain's noble blood. Kain is not shown to physically transform - merely peoples perception of him changes - It is unclear if they would see the lighter skinned, white armored Kain from the opening.
Vorador hints that Kain may have retained the Disguise or Beguile abilities (or both) in Blood Omen 2, saying he can "disguise [his] presence" - Kain himself even comments that "these Humans never look twice in my direction".
- Kain's powers / vamp design for SR series questions at DCabDesign (by Razielim) post #7 (by Daniel Cabuco)